/*
* main(): This function is the entry point for the server program of Share Your Playlist application.
* This function creates the upload and download sockets and waits for client connections.
* We have implemented all the 3 methods used in concurrency in servers namely:
* 1. Multi-process approach using fork() for handling upload and download functionalities
* 2. Non-blocking I/O using select() for monitoring two ports on server
* 3. Multi-threaded approach for data redundancy between servers
*/
int main(int argc, char **argv) {
struct sockaddr_in sockserv;
unsigned int alen;
int upload_sock, download_sock, i, slave_sock, fds[2], *fd = NULL;
struct sockaddr *addr;
socklen_t *addrlen;
//binds sockets for upload and download functionality
upload_sock = passiveTCP(UPLOAD_PORT);
download_sock = passiveTCP(DOWNLOAD_PORT);
printf("Upload sock : %d\n", upload_sock);
printf("Download sock : %d\n", download_sock);
fds[0] = upload_sock;
fds[1] = download_sock;
while (1) {
//calls function to identify which port client connected to
slave_sock = network_accept_any(fds, 2, &fd);
//Initializing thread attributes for prstats thread
(void) pthread_attr_init(&ta);
(void) pthread_attr_setdetachstate(&ta, PTHREAD_CREATE_DETACHED);
(void) pthread_mutex_init(&stats.st_mutex, 0);
/*if(pthread_create(&th, &ta, (void * (*)(void *))prstats, 0) < 0)
fatal("prstats thread failed");*/
//Based on socket that obtained the connection, we use multi-process approach using fork() to provide concurrency
//Based on upload/download, the respective functions are called in the child processes.
if (*fd == upload_sock) {
switch (fork()) {
case 0:
close(*fd);
exit(handleUpload(slave_sock));
default:
close(slave_sock);
break;
}
}
if (*fd == download_sock) {
switch (fork()) {
case 0:
close(*fd);
exit(handleDownload(slave_sock));
default:
close(slave_sock);
break;
}
}
}
}
int main(int argc, char *argv[])
{
#ifdef _WIN32
nodaemon = 1;
WSADATA wsadata;
WSAStartup(0x0202, &wsadata);
#endif
SOCKET s = INVALID_SOCKET;
s = socket(AF_INET6, SOCK_STREAM, 0);
if (s != INVALID_SOCKET)
{
HaveIPv6Stack = 1;
close(s);
s = INVALID_SOCKET;
}
s = socket(AF_INET, SOCK_STREAM, 0);
if (s != INVALID_SOCKET)
{
HaveIPv4Stack = 1;
close(s);
}
int o;
const static char* const optstring = "u:g:L:p:i:P:l:r:feD46";
for (opterr = 0; ( o = getopt(argc, argv, optstring) ) > 0; ) switch (o)
{
case '4':
if (!HaveIPv4Stack)
{
fprintf(stderr, "Fatal: Your system does not support %s.\n", cIPv4);
return !0;
}
v4required = 1;
break;
case '6':
if (!HaveIPv6Stack)
{
fprintf(stderr, "Fatal: Your system does not support %s.\n", cIPv6);
return !0;
}
v6required = 1;
break;
case 'p':
fn_pid = optarg;
break;
case 'i':
fn_ini = optarg;
break;
case 'l':
fn_log = optarg;
break;
case 'L':
maxsockets++;
break;
case 'f':
nodaemon = 1;
logstdout = 1;
break;
case 'D':
nodaemon = 1;
break;
case 'e':
logstdout = 1;
break;
case 'r':
RandomizationLevel = atoi(optarg);
if (RandomizationLevel < 0 || RandomizationLevel > 2) RandomizationLevel = 1;
break;
case 'g':
if (GetGid()) return !0;
break;
case 'u':
if (GetUid()) return !0;
break;
case 'P':
break;
default:
Usage(argv[0]);
return !0;
}
if (optind != argc)
{
Usage(argv[0]);
return !0;
}
int allocsockets = maxsockets ? maxsockets : 2;
SocketList = malloc(allocsockets * sizeof(SOCKET));
#if defined(__BSD__) || defined(__APPLE__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__DragonFly__) || defined(__OpenBSD__)
optind = 1;
optreset = 1; // Makes BSD getopt happy
#else
optind = 0; // Makes GLIBC getopt happy
#endif
for (opterr = 0; ( o = getopt(argc, argv, optstring) ) > 0; ) switch (o)
{
case 'L':
AddSocketAddress(optarg);
break;
case 'P':
defaultport = optarg;
break;
default:
break;
}
if (!maxsockets)
{
if (HaveIPv6Stack && (v6required || !v4required)) AddSocketAddress("::");
if (HaveIPv4Stack && (v4required || !v6required)) AddSocketAddress("0.0.0.0");
}
if (!numsockets)
{
fprintf(stderr, "Fatal: Could not listen on any socket.\n");
return !0;
}
#ifndef _WIN32
if ((gid != INVALID_GID && setgid(gid)) || (uid != INVALID_GID && setuid(uid)))
{
fprintf(stderr, "Fatal: setgid/setuid for %s failed.\n", optarg);
return !0;
}
#endif
if (RandomizationLevel == 1)
{
int i;
srand((unsigned int)time(NULL));
int serverType = rand() % _countof(HostOS);
int16_t lang = LcidList[rand() % _countof(LcidList)];
for (i = 0; i < _countof(RandomPid); i++)
{
GenerateRandomPid(AppList[i].guid, RandomPid[i], serverType, lang);
}
}
#ifndef _WIN32 // Windows has no fork or signal handling
if ( !nodaemon) if (daemon(!0, logstdout))
{
fprintf(stderr, "Fatal: Could not daemonize to background.\n");
return errno;
}
{
struct sigaction sa =
{
.sa_handler = SIG_IGN,
.sa_flags = SA_NOCLDWAIT
};
if ( sigemptyset(&sa.sa_mask) || sigaction(SIGCHLD, &sa, 0) )
return errno;
}
#endif
logger("KMS emulator started successfully\n");
if (fn_pid)
{
FILE *_f = fopen(fn_pid, "w");
if ( _f ) {
fprintf(_f, "%u", getpid());
fclose(_f);
}
else
{
logger("Warning: Cannot write pid file.\n");
}
}
srand( (int)time(NULL) );
RpcAssocGroup = rand();
for (;;)
{
socklen_t len;
struct sockaddr_storage addr;
SOCKET s_client;
for (;;) if ( (s_client = network_accept_any(SocketList, numsockets, NULL, NULL)) < 0 )
{
if ( errno != EINTR )
return errno;
}
else break;
RpcAssocGroup++;
len = sizeof addr;
if (getsockname(s_client, (struct sockaddr*)&addr, &len) ||
getnameinfo((struct sockaddr*)&addr, len, NULL, 0, RpcSecondaryAddress, sizeof(RpcSecondaryAddress), NI_NUMERICSERV))
{
strcpy(RpcSecondaryAddress, "1688"); // In case of failure use default port (doesn't seem to break activation)
}
RpcSecondaryAddressLength = LE16(strlen(RpcSecondaryAddress) + 1);
#ifndef _WIN32
int pid;
if ( (pid = fork()) < 0 )
return errno;
else if ( pid )
close(s_client);
else
#endif
{
char ipstr[256], text[256];
struct timeval to = {
.tv_sec = 60,
.tv_usec = 0
};
setsockopt(s_client, SOL_SOCKET, SO_RCVTIMEO, (char*)&to, sizeof(to));
setsockopt(s_client, SOL_SOCKET, SO_SNDTIMEO, (char*)&to, sizeof(to));
len = sizeof addr;
if (getpeername(s_client, (struct sockaddr*)&addr, &len) ||
!ip2str(ipstr, sizeof(ipstr), (struct sockaddr*)&addr, len))
{
*ipstr = 0;
}
char *connection_type = addr.ss_family == AF_INET6 ? cIPv6 : cIPv4;
static char *const cAccepted = "accepted";
static char *const cClosed = "closed";
static char *const fIP = "%s connection %s: %s.\n";
CloseAllListeningSockets();
sprintf(text, fIP, connection_type, cAccepted, ipstr);
if (*ipstr) logger(text);
RpcServer(s_client);
#ifdef _WIN32
shutdown(s_client, SD_BOTH);
#endif
close(s_client);
sprintf(text, fIP, connection_type, cClosed, ipstr);
if (*ipstr) logger(text);
#ifndef _WIN32
return 0;
#endif
}
}
unlink(fn_pid);
CloseAllListeningSockets();
return 0;
}